Spring Boot实现文件上传

# 配置上传参数
spring:  
    http:
        multipart:
          enabled: true # 默认支持文件上传
          file-size-threshold: 0 # 支持文件写入磁盘
          max-file-size: 50MB # 最大文件上传大小
          max-request-size: 100MB  # 最大支持请求大小

<form method="POST" enctype="multipart/form-data" action="/index/fileupload">

    文件：<input type="file" name="lemonFile"/>

    <input type="submit" value="上传"/>

</form>

package com.lemon.springboot.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.IOException;
import java.util.UUID;

/**
 * @author lemon
 */
@Controller
@RequestMapping("/index")
public class IndexController {

    private static final Logger logger = LoggerFactory.getLogger(IndexController.class);

    @RequestMapping
    public String index() {
        logger.info("访问主页");
        return "index";
    }

    @RequestMapping(value = "/fileupload", method = RequestMethod.POST)
    @ResponseBody
    public String upload(@RequestParam("lemonFile") MultipartFile file) {
        logger.info("文件上传方法访问成功");
        if (file.isEmpty()) {
            return "文件上传失败";
        }
        // 获取文件名
        String originalFilename = file.getOriginalFilename();
        logger.info("上传文件的文件名是：" + originalFilename);

        // 获取文件后缀名
        String suffixName = originalFilename.substring(originalFilename.lastIndexOf("."));
        logger.info("上传文件的后缀名是：" + suffixName);

        // 设置文件上传绝对路径
        String filePath = "/Users/lemon/IdeaProjects/springboot/upload/";

        // 获取UUID名称
        String fileName = UUID.randomUUID() + suffixName;

        // 获取上传文件的File对象
        File dest = new File(filePath + fileName);

        // 开始上传
        if (!dest.getParentFile().exists()) {
            dest.getParentFile().mkdirs();
        }
        try {
            file.transferTo(dest);
            logger.info("上传成功");
            return "上传成功";
        } catch (IllegalStateException | IOException e) {
            e.printStackTrace();
            logger.info(e.getMessage());
        }
        return "上传失败";
    }
}